Analyzing the Results of Demonstration Studies - Evaluation Methods in Biomedical Informatics - page 245

Scenario 3:

Mode of receiving advice

Hospital All patients By request None

A G1 G2 G3

B G4 G5 G6

Scenario 4:

Intervention

Services Reminders Control

A G1

B G2

C G3

D G4

E G5

F G6

G G7

H G8

I G9

J G10

K G11

L G12

Scenario 5:

Studied by

Body system Computer Lecture

CV G1 G2

GI G2 G1

Self-Test 8.2
1. Accuracy = (145 + 74)/298 = 0.73; sensitivity = 145/200 = 0.72; speci-

ficity = 74/98 = 0.75. (b) chi-square = 61.8 (highly significant with df = 1).

(c) 0.44.

2. By inspection of the ANOVA table, the only significant effect is the
main effect for the advice mode. There is no interaction between hospital
and group, and there is no difference, across groups in mean charges for the
two hospitals. Examining the table of means and standard deviations, we
see how the means are consistent across the two hospitals. The mean for all

k=